diff --git a/ProjectEulerCS/ProblemSelection.cs b/ProjectEulerCS/ProblemSelection.cs
index d2d84fc..3c07071 100644
--- a/ProjectEulerCS/ProblemSelection.cs
+++ b/ProjectEulerCS/ProblemSelection.cs
@@ -31,7 +31,7 @@ namespace ProjectEulerCS{
 		//Holds the valid problem numbers
 		private static readonly List<int> _PROBLEM_NUMBERS = new List<int>()
 				{ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
-				 10, 11};
+				 10, 11, 12};
 		public static System.Collections.Generic.List<int> PROBLEM_NUMBERS{
 			get { return _PROBLEM_NUMBERS; }
 		}
@@ -51,6 +51,7 @@ namespace ProjectEulerCS{
 				case  9: problem = new Problem9(); break;
 				case 10: problem = new Problem10(); break;
 				case 11: problem = new Problem11(); break;
+				case 12: problem = new Problem12(); break;
 			}
 			return problem;
 		}
diff --git a/ProjectEulerCS/Problems/Problem12.cs b/ProjectEulerCS/Problems/Problem12.cs
new file mode 100644
index 0000000..50cf10d
--- /dev/null
+++ b/ProjectEulerCS/Problems/Problem12.cs
@@ -0,0 +1,128 @@
+//ProjectEuler/ProjectEulerCS/src/Problems/Problem12.cs
+//Matthew Ellison
+// Created: 08-24-20
+//Modified: 08-24-20
+//What is the value of the first triangle number to have over five hundred divisors?
+//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/CSClasses
+/*
+	Copyright (C) 2020  Matthew Ellison
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+
+using System.Collections.Generic;
+
+
+namespace ProjectEulerCS.Problems{
+	public class Problem12 : Problem{
+		//Variables
+		//Static variables
+		private const int GOAL_DIVISORS = 500;
+
+		//Instance variables
+		private long sum;	//The sum of the numbers up to counter
+		private long counter;	//The next number to be added to sum
+		private List<long> divisors;	//Holds the divisors of the triangular number sum
+		public long TriangularNumber{
+			get{
+				if(!solved){
+					throw new Unsolved();
+				}
+				return sum;
+			}
+		}
+		public long LastNumberAdded{
+			get{
+				if(!solved){
+					throw new Unsolved();
+				}
+				return counter - 1;
+			}
+		}
+		public List<long> DivisorsOfTriangularNumber{
+			get{
+				if(!solved){
+					throw new Unsolved();
+				}
+				return divisors;
+			}
+		}
+		public int NumberOfDivisors{
+			get{
+				if(!solved){
+					throw new Unsolved();
+				}
+				return divisors.Count;
+			}
+		}
+
+		//Functions
+		//Constructor
+		public Problem12() : base("What is the value of the first triangle number to have over five hundred divisors?"){
+			sum = 1;
+			counter = 2;
+			divisors = new List<long>();
+		}
+		//Operational functions
+		//Solve the problem
+		public override void solve(){
+			//If the problem has already been solved do nothing and end the function
+			if(solved){
+				return;
+			}
+
+			//Setup the other variables
+			bool foundNumber = false;	//To flag whether the number has been found
+
+			//Start the timer
+			_timer.start();
+
+			//Loop until you fin the appropriate number
+			while((!foundNumber) && (sum > 0)){
+				divisors = mee.Algorithms.getDivisors(sum);
+				//If the number of divisors is correct set the flag
+				if(divisors.Count > GOAL_DIVISORS){
+					foundNumber = true;
+				}
+				//Otherwise add to the sum and increase the next number
+				else{
+					sum += counter;
+					++counter;
+				}
+			}
+
+			//Stop the timer
+			_timer.stop();
+
+			//Throw a flag to show the problem is sovled
+			solved = true;
+
+			//Save the results
+			_result = "The triangular number " + sum + " is the sum of all number >= " + (counter - 1) + " and has " + divisors.Count + " divisors";
+		}
+		//Reset the problem so it can be run again
+		public override void reset(){
+			base.reset();
+			sum = 1;
+			counter = 2;
+			divisors.Clear();
+		}
+	}
+}
+
+/* Results:
+The triangular number 76576500 is the sum of all number >= 12375 and has 576 divisors
+It took an average of 270.496 milliseconds to run this problem through 100 iterations
+*/